Copying 360 game saves

Is it pos to copy game saves from one hard drive to another,
Also is it pos to copy update files from one hdd to another for example
i have an unmodded 360 which is connected to xbox live which can play xvid and avi through the media player and i have a modded one banned from live, can i extract the files that allow me to play the avi`s and put on banned xbox.
Cheers